60results about How to "Small out of roundness" patented technology

The invention provides a three-frequency-band high-gain omnidirectional dipole antenna comprising a three-frequency oscillator array, balanced feeder lines, a first dielectric plate, a second dielectric plate, and a third dielectric plate. The first dielectric plate, the second dielectric plate, and the third dielectric plate are arranged successively from top to bottom. The balanced feeder lines are arranged at the top surface and the bottom surface of the second dielectric plate and are printed along the axis direction of a three-frequency oscillator unit. The balanced feeder lines are parallel dual-line transmission lines. The three-frequency oscillator units in the three-frequency oscillator array are printed at the first dielectric plate and the third dielectric plate; and feeding points among all three-frequency oscillator units are connected by the balanced feeder lines. The three-frequency oscillator units consist of upper arms and lower arms, wherein the upper arms and the lower arms are arranged in a mirror symmetry mode. The upper arms and the lower arms include first branches, second branches, and third branches, wherein the first, second, and third branches are arranged along parallel axes; the second branches and the third branches are arranged at the two sides of the first branches symmetrically and the bottoms are connected into one by horizontal branches; and balanced feeding points are formed at central protrusions of the upper arm and the lower arm. The three-frequency-band high-gain omnidirectional dipole antenna has advantages of high gain, omnidirectivity, high efficiency, small size, and low cost; and an effective or benefical reference is provided for an optimized design of other multi-frequency or broadband high-gain omnidirectional array antennas.

The invention discloses an omnidirectional antenna and an omnidirectional antenna array. The omnidirectional antenna comprises a dielectric substrate and a first omnidirectional radiation unit, wherein the first omnidirectional radiation unit comprises a main dipole, a parasitic dipole and a metal bottom plate; the main dipole comprises a first metal sheet printed on one surface of the dielectric substrate and a second metal sheet vertical to the dielectric substrate and inserted in the first metal sheet; the first metal sheet, the parasitic dipole and the metal bottom plate are printed on one surface of the dielectric substrate; the first metal sheet is printed in front of the metal bottom plate; and the parasitic dipole is printed in front of the first metal sheet. According to the omnidirectional antenna of the invention, through arranging the parasitic dipole, the bandwidth of the antenna is expanded, and non-circularity of the antenna is reduced; and in addition, by adopting the main dipole in a three-dimensional structure, a larger bandwidth can be provided.

The invention discloses a broadband horizontally polarized omnidirectional antenna, which comprises a circular dielectric substrate, a broadband microstrip feed network printed at the upper part of the dielectric substrate and a metal grounding plate printed at the lower part of the dielectric substrate, wherein gaps are etched in the metal grounding plate; an SMA connector is arranged on the metal grounding plate at the lower part of the center of the dielectric substrate; two groups of crossed gaps which are arranged at intervals, are the same in size, are alternately arranged along the circumference and are distributed in a central symmetry manner are etched in the circumference surface of the metal grounding plate; a power divider is arranged at the center of the broadband microstrip feed network; impedance transformers which extend along the center of the power divider are distributed along the circumference surface of the broadband microstrip feed network in a radial manner; andmicrostrip broadband baluns extending at a right angle are arranged at the end parts of the impedance transformers. According to the broadband horizontally polarized omnidirectional antenna, the current path is changed, the volume of the antenna is reduced, the impedance bandwidth of the antenna is expanded, the out-of-roundness of a horizontal diagram is reduced, impedance matching in a working band is improved and the efficiency of the antenna is improved. The broadband horizontally polarized omnidirectional antenna is simple and compact in structure, convenient to process and low in cost.

The invention relates to a winding drum overlaying technique of a wire drawing machine, comprising the following steps of: before welding a winding drum, firstly turning a working surface of the winding drum according to abrasion requirements; fixing the winding drum on a rotary shaft, when mounting, positioning as an inner hole of the winding drum, adjusting the position to lead the working surface of the winding drum to be vertical to the position of an overlaying gun; preheating; overlaying; keeping warm after overlaying; and naturally cooling to room temperature. The invention has the advantages that an overlaying technique is used, the thickness of overlaying can be set randomly, after overlaying, the winding drum can be fine-processed, the deformation and the ellipticity of the winding drum can be minimal; and the invention has simple processing and convenient operation.

The invention provides a method for generating omni-directional circularly polarized vortex electromagnetic waves, and solves the technical problems that in the prior art, omni-directional vortex electromagnetic waves are low in gain, and circular polarization is difficult to achieve. The implementation process comprises the following steps of: designing the lens shape of a cylindrical metasurfacelens component; setting parameters of the lens component; calculating expected vortex electromagnetic wave phase distribution and metal layer geometric rotation angle distribution of the initial model; establishing a lens component initial model and performing full-wave simulation; calculating convergence phase distribution and metal layer geometric rotation angle distribution of a final model; and obtaining a final model of the lens component, and carrying out full-wave simulation verification on the final model. A planar metasurface lens formed by periodically arranging transmission unit structures is conformal to a cylindrical surface to form a cylindrical metasurface lens component. The method for generating omni-directional circularly polarized vortex electromagnetic waves has the advantages of the relatively high gain, the relatively high circular polarization purity and the simple feeding, and can be applied to the field of communication.

The invention provides an omnidirectional indoor distribution antenna applied to 5G communication. The omnidirectional indoor distribution antenna comprises horizontal polarization units, a vertical polarization unit, a dielectric plate and a feed network, wherein the horizontal polarization units are located on the dielectric plate; the dielectric plate is in a round form; the horizontal polarization units are uniformly arranged outwards by taking the center of the dielectric plate as the circle center; the vertical polarization unit is located at the circle center of the horizontal polarization units and is vertical to the horizontal polarization units, that is to say, the vertical polarization unit is vertical to the dielectric plate; each horizontal polarization unit comprises an SMA feed head, a 1-to-8 feed network, eight pairs of radiation dipoles, an FR4 dielectric plate, a ground plane shaped like the sun, eight pairs of parasitic patches and eight pairs of leading units; and the vertical polarization unit comprises the SMA feed head, the ground plane shaped like the sun and a vertical polarization radiation structure shaped like a vase. The antenna has the characteristicsof a low profile, a large impedance bandwidth, high isolation, high gain, low out-of-roundness and low cross polarization.

The invention discloses a production line for a steel wire glass fiber reinforced composite pipe. The production line comprises an inner pipe extruding machine. The downstream part of the inner pipe extruding machine is provided with a first cooling device. The downstream part of the first cooling device is provided with a first traction machine. The downstream part of the first traction machine is provided with a glass fiber belt winding unit. The downstream part of the glass fiber belt winding unit is provided with a steel wire winding unit. The downstream part of the steel wire winding unitis provided with a first air blower. The downstream part of the first air blower is provided with a gluing device. The downstream part of the gluing device is provided with a sizing cooling draught fan used for cooling the surface of a glued pipe. The downstream part of the sizing cooling draught fan is provided with an outer pipe extruding machine. The downstream part of the outer pipe extrudingmachine is provided with a second cooling device. The downstream part of the second cooling device is provide d with a second traction machine, and the downstream part of the second traction machineis provided with a pipe cutting machine. By means of the production line for the steel wire glass fiber reinforced composite pipe, steel wire glass fiber reinforced composite pipes can be continuouslyand automatically produced, the grade of the pressure of the produced steel wire glass fiber reinforced composite pipes is higher, and the performance is more stable.

Drawing methods and drawing furnaces for drawing an optical fiber with small non-circularity by simple drawing system are provided. An optical fiber preform is received into a muffle tube and heated by a primary heater placed to surround the muffle tube. The optical fiber preform is heated such that a starting position of a meniscus portion is higher in its position than the top of the primary heater, wherein the meniscus portion is created at the bottom portion of the optical fiber preform.

The invention belongs to the technical field of design for antennas, and relates to a high-gain broadband omnidirectional antenna. The high-gain broadband omnidirectional antenna comprises a half-wave dipole antenna, a reflector plate, a matching platform and a coaxial cable. The matching platform is in the shape of a circular truncated cone with lower end face open and inside hollow, and a circular hole is arranged on the upper end face of the matching platform. The half-wave dipole antenna is cylindrical, the lower half portion of the half-wave dipole antenna is disposed in the circular hole of the matching platform, and the upper half portion of the half-wave dipole antenna exposes from the upper end face of the circular hole. The circular reflector is arranged above the half-wave dipole antenna, the diameter of the reflector plate is equal to that of the lower end face of the matching platform, the reflector plate and the matching platform are concentric and arranged at positions corresponding to each other up and down. The coaxial cable is arranged below the half-wave dipole antenna, and the coaxial cable is connected with the half-wave dipole antenna to form a feed port. The high-gain broadband omnidirectional antenna solves technical problems that existing omnidirectional antennas are incapable of meeting requirements of indexes such as frequency bands, feed network, out-of-roundness of directional diagrams, wave beam direction and gain performance, and has the advantages wide frequency band, simple feed network, low out-of-roundness of directional diagrams, stable wave beam direction and high gain.

The invention provides a high-refractivity, light-reflecting microspheric glass, comprising the following components in gram molecular percent: SiO2 1-12, B2O3 1.5-11, TiO2 20-55, BaO2 5-56, CaO 2-10, ZnO 0.3-10 and Sb2O3 0.1-2. And it has characters of high reflection brightness, no harmful components, and safety and no pollution.

The invention relates to a quartz optical fiber and a preparation method and device thereof, and the preparation method comprises the steps: coating the surface of the quartz bare optical fiber with glass-ceramic liquid before the temperature of drawn quartz bare optical fiber is reduced to the glass-transition temperature of the quartz bare optical fiber, so as to form a glass-ceramic coating layer; and after cooling, coating the surface of the glass ceramic coating with an organic coating to form an organic coating layer, so as to obtain the quartz optical fiber, wherein the expansion coefficient of the glass ceramic is smaller than 5*10<-7>/DEG C, and the melting temperature is 1200-1400 DEG C, and the core layer and the sheath layer of the quartz bare optical fiber are made of quartz glass materials. According to the invention, the glass-ceramic coating layer with low expansion coefficient is formed on the surface of the quartz bare optical fiber by adopting a high-temperature online coating method, so that the tensile strength of the quartz optical fiber is improved.

The invention specifically relates to a directional diagram reconfigurable antenna based on a switchable director, and belongs to the technical field of antennas. The antenna comprises a substrate which comprises an upper layer and a lower layer which are composed of microwave dielectric substrates; a dielectric resonator which is adhered to the upper surface of the upper layer; a pair of symmetrical metal arms surrounding the outer side of the dielectric resonator and etched on the upper surface of the upper layer; a power divider etched on the lower surface of the lower layer; a pair of switchable directors which are arranged in the upper surface of the upper layer, surround the periphery of the dielectric resonator and are symmetrical, wherein the distance from the switchable director to the center of the dielectric resonator is greater than the distance from the metal arm to the center of the dielectric resonator; metal ground arranged between the upper layer and the lower layer of the substrate, wherein the vertical projection area of the metal ground on the substrate is larger than the vertical projection area of the dielectric resonator on the substrate; and metal through holes are formed in the surfaces of the upper layer and the lower layer of the substrate. The metal arms penetrate through the substrate from top to bottom through the metal through holes and are connected with the power divider; and the metal arms and the power divider form a feed structure of the antenna.

The invention provides an omnidirectional WLAN (Wireless Local Area Networks) antenna with common-mode current suppression. The antenna comprises a radiation structure and a coaxial line, the radiation structure is formed by a first radiation unit, a second radiation unit and a third radiation unit (13) which have the same structure; each radiation unit is provided with three feed ports with the same structure, a first polygonal groove, a second polygonal groove and two same cutting angles; metal branches are arranged between the first polygonal grooves and the second polygonal grooves, the centers of the metal branches are provided with gaps; one end of the coaxial line is led in along one sides of the feed ports and is distributed at the edges of the first radiation units, and the otherend of the coaxial line is led out along the opposite sides of the feed ports and is connected with an SMA joint. The omnidirectional WLAN antenna can suppress the common mode current on the outer surface of the feed coaxial line and can reduce the distortion of the antenna directional diagram while meeting the performance of the omnidirectional WLAN antenna, and can be used for a wireless local area network communication system.